The invention relates generally to power generation and the efficient recovery of carbon dioxide. More particularly, the invention relates to the integration with carbon dioxide separation with efficient heat recovery and oxygen consumption.
Power generation systems that combust fuels containing carbon, for example fossil fuels, produce carbon dioxide (CO2) as a byproduct as carbon is converted to CO2 during the combustion process. Removal or recovery of the carbon dioxide (CO2) from power generation systems, such as from the exhaust of a gas turbine, is generally not economical due to low CO2 content and low (ambient) pressure of the exhaust. Therefore, unfortunately, the exhaust containing the CO2 is typically released to the atmosphere, and does not get captured and sequestered into oceans, mines, oil wells, geological saline reservoirs, and so on.
In any power generation cycle, once the oxidant is compressed for the combustion process, it is desirable to use all chemical energy of the compressed oxidant (that is the oxygen content). In conventional power plants, the exhaust released to the atmosphere typically contains a significant amount of oxygen. Even in power plants that separate CO2 before discharging the exhaust into the atmosphere, the exhaust still contains some amount of oxygen. The CO2 lean stream containing oxygen that is discharged into atmosphere after separation of CO2 is typically at a temperature and oxygen levels, which temperature and oxygen levels are too low for the stream to be used in a combustion process representative of an efficient gas turbine.
Therefore there is a need to effectively separate CO2 and simultaneously utilize the oxygen content in the discharge stream from a power plant to increase the efficiency of the power plant.